NPR just posted a graphical timeline showing the longest lived organisms on Earth and when they were born in history. Lifespans range from King’s lomatia at 43,000 years to Galapagos tortoises at 150 years.

We have just released LigerCat v. 2.1 – with new features and faster search. LigerCat it is a tool that allows you to search PubMed using words or even a DNA/protein sequence. The articles retrieved are processed to create a tag cloud showing an overview of important concepts and trends. The Medical Subject Headings or MeSH descriptors are combined and weighted by frequency (more frequent terms have a larger font size) to create the cloud. Clicking on one or more MeSH descriptors in the tag cloud adds it to the box on the right of the cloud and LigerCat searched PubMed for those terms instantly. Selecting more than one term finds articles tagged with all selected MeSH descriptors.

MeSH Cloud and Publication History for Alzheimer Disease

New features

• Publication History graphs – In the Articles Search a Publication History graph is displayed in addition to the MeSH tag cloud. This is an interactive graph. Mousing over the graph will highlight years and display the number of articles from that year that your search retrieved. Clicking on the bar for that year performs the search in PubMed and takes to that result page. In the Genes Search, the graph will not take you to PubMed but you still can see how many articles related to the query sequence were published in each year.
• Code snippet available so you can put a MeSH cloud on your blog or home page

Just click on the Share tab to get a code snippet for the cloud.

The embedded Alzheimers Disease cloud looks like this:

Steve Austad’s paper in Journal of Comparative Pathology (PubMed), Methusaleh’s Zoo: How Nature provides us with Clues for Extending Human Health Span, promotes the idea that “exceptionally long-lived organisms have important roles to play in our future understanding of the causal mechanisms and modulation of ageing.” Austad writes that most of what is known about the aging process is derived from experiments performed on short-lived laboratory species like Drosophila melanogaster, Caenorhabditis elegans and Mus musculus. He suggests that studying long-lived species such as naked mole-rats (Heterocephalus glaber) and some bats like Myotis brandti that lives for 41 years, might offer insight into the mechanisms of the aging processes. There are many more species to discover and study. As Austad concludes: “However, with the dramatic acceleration in our genome sequencing capability, it is likely that new investigatory tools for these species of exceptional gerontological interest will be developed at an accelerating pace. The role of Methusaleh’s Zoo in ageing research is likely to blossom in the near future.”

Scientists from Université de Rennes use an usual organism for their research, the sub-Antarctic wingless fly, Anatalanta aptera. This fly is interesting because it has a long imaginal life thus offering a good model to study evolution and senescence. A study recently published in Biology Letters showed that contrary to expectation older flies recovered better after experiencing cold temperatures. According to the authors, “our results both challenge the generality of the prediction that ageing impairs rather than improves performance in thermal biology and highlight the scarcity of studies on the subject.”

The new gene discovered in mouse (Mus musculus), Rps23r1, decrease levels of toxic proteins that are linked to the formation plaques and tangles in the brains of Alzheimers disease patients. Published today in Neuron and the result of a worldwide collaboration of seven institutions, the research identifies the new gene and demonstrates how it reduces the levels of protein phosphorylation of key proteins involved in Alzheimers disease pathology. “Our studies reveal a new target/pathway for regulating AD pathologies and uncover a retrogene and its role in regulating protein kinase pathways,” write the authors in the articles abstract. Read more at Eureka Alert, Burnham Institute for Medical Research, Science Daily.

Longevity and the process of aging are topics of perennial human interest as expressed by explorers like Alexander the Great and Juan Ponce de Leon searching for a river or spring to heal or reverse the process of aging or by modern scientists studying biology of aging.  Just a short walk across the MBL campus from EOL’s Biodiversity Informatics group resides the team charged with creating the Biology of Aging portal.

Read the full post here

A recent paper by Christina Dagmar Buesching and colleagues demonstrate two different endocrinological phenotypes in  wild European badgers, Meles meles. Type 1 males lower their testosterone levels after the end of the main mating season in winter, thus presumably saving energy and maintaining good body condition and low parasite loads, while type 2 continue to maintain high levels of circulating sex-steroids, staying in reproductive condition until late summer/ autumn. The researches found some evidence for the hypothesis that Type 1 males suffer higher early mortality rates and thus a lower life expectancy.

MeSH Cloud for Ursus maritimus

The LigerCat-generated MeSH cloud for polar bear shown above is just one of the over 50,000 species specific clouds now displayed at the Encyclopedia of Life. If a species has been mentioned in the abstract or title of an article indexed by Medline, LigerCat – a PubMed exploration tool – is able to create a species-specific tag cloud displaying the Medical Subject Headings (MeSH) that have also been attributed to those articles. These MeSH clouds can be used to explore the biomedical literature that specifically applies to the organism chosen. This collaboration between the Biology of Aging Portal and EOL helps make EOL pages more relevant to scientists studying aging.

Biomedical Terms

You can find the MeSH clouds under the Table of Contents Chapter Heading – Biomedical Terms on EOL Species Pages.

The New York Times reported yesterday that drugs that simulate the effects of calorie reduction on aging are now under clinical trials. The drugs mentioned, resveratrol (the bioactive component in grapes and red wine) and small molecule activators of sirtuin are being tested in combination by Sirtris Pharmaceuticals of Cambridge, MA. The article also describes the idea of intrisic aging and the evolutionary theory of aging. At the time of this posting there were 137 comments to the article.

Caleb Finch’s (University of Southern California) review: Update on Slow Aging and Negligible Senescence – A Mini-Review, recently published in the journal Gerontology, explains the concept of negligible senescence he developed about 20 years ago. Since formulating this hypothesis he has been searching for organisms that display slow aging. In this review he discusses several long-lived species: turtles – Blanding’s turtle  (Emydoidea blandingii), painted turtle  (Chrysemys picta), the fish genus  Sebastes also called rockfish, the naked mole-rat  (Heterocephalus glaber), and human centarians (Homo sapiens).